Infreville



(No Model.)

G. D-INPREVILLE.

. DYNAMO TBLEGRAPHY.

No. 265,488. Patented 0015.3, 1882.

[F /572e,)" em,- f I [nvenor UNITED STATES PATENT Orrrca.

GEORGES DINFREVILLE, OF NEW YORK, N. Y., ASSIGNOR TO THE \VESTERN UNION TELEGRAPH COMPANY, OF SAME PLACE.

DYNAMO-TELEGRAPHY.

SPECIFICATION forming part of Letters Patent No. 265,488, dated October 3, 1882.

Application filed April 27, 1881. (No model.)

1'0 all whom it may concern: vided for such line. However, upon breaking Beit known that [,GEORGES DINFREVILLE, a main-line circuit the electro-magnet controlof the city, county, and State of New York, lingits shunt-switch permits the closing ot'said have made a new and useful improvement in shunt-conductor. Each telegraph-line practithe art of applying dynamo-electric machines cally joins, for the purpose I have in view, the

for telegraphic purposes, of which the i'ollowtwo opposite poles by the dynamo-machine,and ing is a specification, reference being bad to each corresponding normally-open shunt-cirthe accompanying diagram. cuit constitutes a parallel branch circuit, when Dynamo-electric machines whose field-magclosed, of equal resistance, to join the opposite 1o netism is maintained by the currents generated poles of the dynamo-machine. Therefore, as the in their own armatures have heretofore been shuntbranches are only closed when the cordevised to furnish many telegraph-lines conresponding lines are broken, the external renected to the poles of the machine in multiple sistance of the machine must be the same are With electricity by connecting the oppowhether the main lines are broken or closed.

I5 site poles of said dynamo-electric machine with I will now explain my invention by refera shunt-conductor of comparatively high reence to the accompanying diagram. sistance, said resistance for ordinary purposes 1) M represent a dynamo-machine the helibeing intermediate in amount between the low ces of whose fieldanagnets, 1*, are in circuit internal resistance of the dynamo-m achine and with the armature. on and n are brushes of the 20 the higher joint resistance of the main lines machine. a" and'y lead to binding-postsG and connected to the dynamo-machine in multiple 7, respectively. Posts 7 and 6 are joined by arc. a constantly-closed slnint-comlnctor, 8, having In the process ofsending messages upon nora resistance, R. They are also joined by a semally-closed circuit Morse wires the various ries of normally-open shuntconductors, each 25 telegraph-lines connected in multiple are are of which is of a resistance equal to that of its arbitrarily broken and closed, from which fact corresponding telegraph-line. In the diagram the joint resistance of the several lines is renonly one normally-open shunt, s, is shown. dered highly variable. The external resist- Shunt s supplements line Z. Z, P, and other ance of the dynamo-machine consists of the lines should each in like manner he provided 3 joint resistance of the permanently-closed with shnnteoinluetors of the same character. shunt-conductor and telegraph-lines, where- \Vhen all of the keyskk are closed at stations fore if any telegraplrline of the series is bro- A B armature a is held to pole of M and against ken the external resistance of the machine is point 2 to give a signal upon local sounder ls.

correspondingly increased, while its electro- However, uponbreaking the circuitofl, either 35 motive force is greatly diminished. at A or B, armature a will be released and will My invention has for its object the mainclose, through back contact, 1, and armature a,

tenance of a practically constant or unvarying the shunt 8. Resistance R of shunt s is equal external resistance, notwithstanding the arbito or less than the resistance of line I. It trary breaking and closing of the several lines, shunt s were not provided, a break of line 1 4 and to the accomplishment of this end each would obviously increase the external resist- 0 of the telegraph-lines is supplemented at the ance of the machine; but as the breaking ofl dynamo-machine with an additional but norautomaticallysubstitutes thereforartilicialaml mally-open shunt,each shunt, when closed,havparallel branch of equal resistance the extering a resistance equal to the resistance of its nal resistance of the machine inust remain 45 respective line. Each shunt is opened and the same. Z 8 represent at each of the sta- 5 closed by an electromagnetic switch controlle l tions local sounders, brought to action respectby its corresponding main line in such a manively by relays M and M, having armatures a ner that when a main line is closed and a curand a. 3 and 4 are front contact-points of rent is thereon an electro-magnet in the line keys k k, respectively. Connections 10 and 14 5 shall retain the switch to break the shunt proeach represent any ordinary form of circuitwhen the key is not being employed for transmission. The opening and closing of line l by any one of keys 7c 70 will actuate all of the local sounders on the line, and at the same time effeet the closing, and opening of shunts, and thereby maintain a uniform external resistance in respect to the dynamo-machine.

G represents an earth-connection for one pole of the generator, while G shows an earthconnection for line Z, connected to the opposite pole.

What I claim, and desire to secure by Letters Patent, is-

1. Adynamo-electric machinet'ortelegraphic purposes,in combination with a main telegraphline, constituting, when closed, a portion of the external circuit of said dynamo-machine, and a compensating shunt joining the opposite poles of said machine, whose resistance is approximately equal to the resistance of said main line, as specified.

2. Adynamo-electric machine for telegraphic purposes, in combination with a main telegraphline, forming a portion ot' the external circuit of said machine when closed, and a compensating-shuntjoining the opposite poles of said machine, whose resistance is approximately equal to that of the main line, and an automatic line is opened and breaks the shunt when the main line is closed, substantially as specified.

3. Adynamo-electrie machinet'or telegraphic purposes, in combination with one or more main telegraph-lines, each forming a portion of the external circuit of the machine, a corresponding number of shunts joining the opposite poles of the machine, an automatic switch for each shunt, operating to open and close the same as the corresponding main telegraph-line is closed and opened, whereby the external resistance of the dynamo-machine, consisting of the main telegraph-Iines and shunts joining the opposite poles of the machine, may be maintained practically constant as the said telegraph-lines are arbitrarily opened and closed in the process of sending messages.

4. Adynamo-electric machinefor telegraphic purposes, in combination with a telegraph-line fed thereby and a shunt joining the opposite poles of said machine, whose resistance is sub stantially equal to the resistance of the line, as specified.

, GEORGES DINFREVILLE.

Witnesses:

WM. ARNOUX, W, B. VaUsizE, 

